GB/T 39659-2020 in English

GB/T 39659-2020 innovatively proposes a digital coding system based on the symmetric structure of Chinese characters, and realizes efficient input of rare characters through 10 types of structural classification and 5 types of stroke encoding. The standard is applicable to all Chinese characters in the GB 18030 character set and is compatible with commonly used Chinese character input scenarios.

The standard adopts a dual-track encoding mechanism:

1. Structure encoding: 0-9 corresponds to 10 types of Chinese character structures (e.g. generalized symmetry = 0, single character = 7)
2. Stroke encoding: 1-5 corresponds to the five basic strokes of horizontal, vertical, left-falling, dot, and right-falling strokes

The key mapping of mobile devices is different from that of computer devices, so you need to pay attention to the device adaptation rules.

Compared with traditional encoding schemes, this standard has three major breakthroughs:

• Structural feature quantification: the first mathematical description system of Chinese character symmetry is established
• Input efficiency optimization: reducing the number of keystrokes through structural prediction (tests show that the average input of uncommon characters only requires 4 keys)
• Ultra-large character set support: expandable support for CJK extended G-zone characters added in Unicode 13.0

Input method development

It is recommended to adopt a two-level retrieval strategy: first match the structural code to narrow the candidate range, and then accurately locate through the stroke code.

User Training

Key Points:

1. Quick identification of 500+ symmetrical components in Appendix A
2. 25 types of stroke order processing rules that are easy to make mistakes listed in Appendix B